The train station show is over and now it's at the castle.
If park opening is 9am, you can get onto main street at 8am. If park opening is 8am, you can get onto main street at about 7:45am
If there's emh in the morning the show is done at the start of emh, not at the start of regular park hours
Edit: that's how the old show use to be. New morning show is done at regular park opening and not at EMH opening